Novelty yarns or strands are produced by a variety of processes in the textile field and find utility for many specific textile purposes, for example, in the manufacture of draperies, industrial cloths used as reinforcement for resin articles and the like. Many processes have been designed, especially in processing glass fiber strands, to produce decorative effects on textile strands to render them useful in providing bulk for cloth to be woven for decorative purposes as well as cloth woven for industrial purposes such as resin reinforcement.
Thus, in U.S. Pat. No. 3,388,444 a process is described in which glass fiber strands are passed through a texturizing jet at various rates of speed and air under pressure is introduced into the jet to entangle the yarns passing therethrough to produce a bulking effect on the yarn issuing from the jet. In another process, bulky textile yarn is produced by providing a core and effect yarn, each of which travels at different speeds as they are passed through an air jet device to filamentize the fibers of the faster traveling strands and entangle them within the core yarn. A typical process of this type is illustrated in U.S. Pat. No. 3,262,177. Another process for producing a bulky yarn having intermittent bulking along its length is shown in U.S. Pat. No. 3,410,077.
While all of the above processes are useful in producing novel textile strands, a need still exists in the art for a process which will produce efficiently a slubby textile strand in which slubs of good integrity are present. Minimized filament damage caused by breaking filaments during the processing of a strand is also a desired goal in producing slubby strands. Filament damage to strands using the procedures of the prior art often reduces strand strength below an acceptable value. Further, in producing textile strands having slubs thereon, it is a desired goal to produce slubs randomly so that the cloth woven therefrom does not develop a fixed pattern.